Garage doors generally include one of two types of locking systems. As shown in FIGS. 1-4, a first locking system includes one or two slidable lock bars 8 mounted on an interior face of a garage door 2. The door 2 shown in FIG. 1 is a sectional overhead garage door including a plurality of hinged 4 sections 3. The door 2 is slidably mounted in tracks 5 affixed to a building frame 12. One end of each lock bar 8 is connected to a rotatable lock bar disc 9 centrally mounted on an inside face of the door 2. A lock bar guide 13 also supports each lock bar 8 on the door 2. As shown in FIGS. 2 and 3, the lock bar disc 9 is rotated between a locked position in FIG. 2, and an unlocked position in FIG. 3. In the locked position (FIG. 2), the end 8a of each lock bar 8 is received in a slot 7 in its respective door track 5. In the unlocked position (FIG. 3), the ends 8a of the lock bars are retracted from their respective slots 7 in the tracks 5.
A locking mechanism 11 mounted above the lock bar disc 9 selectively permits and prevents rotation of the disc 9. Selective rotation of an actuator lever 11a on the lock 11 causes a bolt 11b to be selectively raised and lowered. As shown in FIG. 2, when the bolt 11b is received in a mating slot 9a in the disc 9, the disc 9 is prevented from rotating, and disc 9 holds the lock bars 8 in engagement with the door track slots 7, thereby preventing the door 2 from being raised in the tracks 5. As shown in FIG. 3, when the bolt 11b is selectively raised, the lock bar disc 9 can be sufficiently rotated to cause the lock bars to retract from the slots 7, thereby permitting the door 2 to be raised. Though the locking system shown in FIGS. 1-4 include two lock bars 8, such systems also may include a single lock bar.
As shown in FIG. 4, the lock 11 includes an exterior keyed opening 13 for permitting the lock 11 to be locked or unlocked with a key 15. An inside handle 10 and an outside handle 17 permit the disc 9 to be selectively rotated from either side of the door 2 when the lock bolt 11b is disengaged from the disc slot 9a. Lock bar locking systems require two door penetrations: a first penetration for the spindle that actuates the disc 9, and a second penetration for the lock 11. Typically, the second opening for the lock 11 is over an inch in diameter and requires the use of a hole saw. Accordingly, such systems are difficult to install, and require careful alignment between the lock bar discs 9 and their mating locks 11. In addition, such systems have an unfinished inside appearance.
A second type of known garage door locking system is shown in FIGS. 5-8. As shown in FIG. 5, so-called “snap latch” systems generally include an actuator 29 with a handle 40 rotatably mounted on an interior face of a garage door 2. At least one cable 28 is connected at one end to the disc 29, and is connected at its other end to a snap latch assembly 30. As shown in FIG. 6, the snap latch assembly 30 includes a base bracket 32 and a latch 34 that is pivotably mounted to the bracket 32 on a pin 33. The latch 34 is biased toward a locked position (as shown in FIG. 6) by a spring 35. In this locked position, the latch 38 engages a strike plate 38 affixed to a fixed member 12 such as a door track or building frame member, thereby preventing relative movement between the door 2 and fixed member 12.
To open the door 2, the actuator 29 is rotated using either the interior handle 40 or exterior handle 39 (FIG. 8) to place tension on the cables 28 as shown in FIG. 7. As the actuator 29 is rotated, the cable 28 pulls the latch 34 from engagement with the striker plate 38, thereby freeing the door 2 to move relative to the frame 12. Such systems typically include a keyed cylinder lock (not shown) in their exterior handles 39 to permit the systems to be locked or unlocked from outside a garage door 2. Unfortunately, such snap latch systems cannot be locked or unlocked from the inside of a garage door 2 and have an unfinished appearance. As indicated in FIG. 8, one advantage of snap latch locking systems is that they require a single door penetration, thereby simplifying installation.
Accordingly, there is a need for an improved locking system that overcomes the shortcomings of known garage door locking systems. Specifically, there is a need for a single locking system that can be used with either lock bars or snap latch cables. Desirably, such a locking system should require only small-diameter door penetrations, and should be lockable from both the inside and outside of a door. In addition, such a locking system should provide an attractive, finished appearance on both sides of a door.